DCBENCH

[chui]

qatmix need a little program for testing dreamcast-overclock.

I make this dreamcast app:
http://www.gp32spain.com/public_ftp/dcbench-dreamcast.rar


My result are:

Primes Benchmark: 14495 msec.

Comparations Benchmark: 16357 msec.

Memory Benchmark: 16772 msec.

Integers Benchmark: 16405 msec.

Floats Benchmark: 15590 msec.


:D

[Kamjin]

Chui,

Could you add read/write access to the VRAM also,
linear 32bit, and a scattered 32bit. I'm curios to see if the mod makes any difference there.

[Eric]

So does this program just give a test of what your system chip is running at and does it help the dreamcast in anyways

[Mental2k]

It just gives info. It's helpful for overclockers and the like. Like when we use benchmark programs on our own pcs to see how they perform, only this gives a detailed breakdown of each component.

[chui]

Chui,

Could you add read/write access to the VRAM also,
linear 32bit, and a scattered 32bit. I'm curios to see if the mod makes any difference there.



I try other bench: memcpys (4KB even) under VRAM->RAM, RAM->VRAM and VRAM->VRAM, but i don't know how make bechmark with linear or scattered.

[chui]

It just gives info. It's helpful for overclockers and the like. Like when we use benchmark programs on our own pcs to see how they perform, only this gives a detailed breakdown of each component.

Also it gives info about your develop enviroment (if you recompile this app). I need a good replacement of newlib mem functions (memcpy, memset,...) because i think these functions aren't the best for dreamcast.

I use newlib-1.12 (+kos patch), binutils-2.15 and gcc-3.4.1 with '-O3 -fomit-frame-pointer -ml -m4-single-only -fno-optimize-sibling-calls -fno-builtin -fno-strict-aliasing -ffast-math'.

Anybody know how optimize for dreamcast?

You can download source code of dcbench and try:
http://www.gp32spain.com/public_ftp/dcbench-src.rar

[qatmix]

Thanks for doing that! *:)

Here are my readings with a 40 mhz crystal added. Its quicker but not by that much. Maybe my wires are to long going to the MB (They are about 30 cm long and its two lengths soldered together, so it might be losign some signals. I do have a capacitot between the %V and GND to ensure a stable current.

Primes * * * * * * * * * * * *: 14553
Compilations * * * * * * *: 16395
Memory Benchmarks *: 16805
Integers benchmarks : 16440
Floats benchmarks * * : 15624

Is there a test that doesnt use VRam as I have only overclocked the CPU and not the PVR so it would be useful to see how this has speeded up the the CPU and Main memory compared to the base DC.
Cheers
Q

[chui]

i've compiled this app for linux with same gnu-compiler (pentium4 underclocked to 850Mhz) and these are my results:

Primes : 3704
Comparations : 4687
Memory : 5222
Integers : 5716
Floats : 14899

Dreamcast is very good for floating points operations and if you compare values:

Benchmark DC PC /
----------------------------------------------
Primes: 14495 / 3704 = 3.913
Comparations: 16357 / 4687 = 3.489
Memory: 16772 / 5222 = 3.211
Integers: 16405 / 5716 = 2.870
Floats: 15590 / 14899 = 1.046 !!!!!


:D

[chui]

Chui,

Could you add read/write access to the VRAM also,
linear 32bit, and a scattered 32bit. I'm curios to see if the mod makes any difference there.



Uff!!! I use simple memcpy (used for SDL, etc.):

RAM->RAM : 2028
RAM->VRAM: 10637
VRAM->RAM: 10638
VRAM->VRAM: 20389

Video buffer is very slow.

Anybody know how speed up video buffer access?

[qatmix]

chui

does the dcbench program now have those speeds as well?

I would like to see teh cpu speed without the pvr slowign it down if possible

(Although Im goign to overclock the PVR a some point)

[chui]

Only new benchmarks uses vram. I've add 4 new benchmarks.

Download and try dcbench update with vram benchmarks:
http://www.gp32spain.com/public_ftp/dcbench-dreamcast.rar

and source code:
http://www.gp32spain.com/public_ftp/dcbench-src.rar

[BlackAura]

Using store queues to copy stuff over to VRAM is faster.

[Alexvrb]

Yeah, most people use SQs or DMA. But you should leave in the current VRAM tests even if you add more, because more information when dealing with an overclocked DC can never hurt.

Oh, and yes, the SH4 is a FP monster. That's why it was so well suited to 3D.

[Alexvrb]

Maybe my wires are to long going to the MB (They are about 30 cm long and its two lengths soldered together, so it might be losign some signals.I'd be curious to see if there was any difference if you used a single shorter wire instead.

[arqueiro]

very cool tests, but can this speed up a game our emulator ? (i mean i we overclock the dc)